There are literally thousands of water plants for use in ponds and streams around the world. Some are more suitable than others to specific environments. That’s where the selection of plants based upon zones comes in. If a plant is hardy in your zone (check with your local nursery if you’re not sure of the zone in which you live), it should do well for you in your water garden.
Here are a few suggestions from our own personal favorites.
HARDY WATER LILIES (Nymphaea spp) These beauties are able to withstand colder temperatures than their tropical cousins can, and they over-winter well so long as the rhizomes remains below ice level. Flower colors are limited to white, pink, yellow, peach, and red, and mature plants bloom from spring through fall, depending on the particular cultivar. Plants grow from 2 - 12 square feet. Plant the crowns 8-24 inches below the water surface. Plant in calm areas where they will receive full sun for best flowering, although the plants themselves can survive in partial shade. Zones 4-10.
TROPICAL DAY-BLOOMING WATER LILIES (Nymphaea spp) These profuse bloomers come in a wide variety of colors and have a heavy fragrance and luxurious foliage. They hold their large, showy blossoms on tall stems several inches above the water and make good cut flowers. Each bloom opens mid-morning, closes in late afternoon, and lasts about four days. As their name suggests, they bloom during the day. Some varieties spread up to 5 feet. Plant them with their crowns 4 - 12 inches below the water surface. Day bloomers prefer sun and flourish in hot weather. They must not be in water cooler than 60° F. Bring them indoors during the cool season. They are winter hardy only in zones 10-11.
TROPICAL NIGHT-BLOOMING WATER LILIES (Nymphaea spp) Night bloomers share the same characteristics as their day-blooming relatives but open their blossoms in early evening and keep them open through mid-morning or longer or until exposed to direct sun. Their evening showiness is highly prized by gardeners who can’t be home during the day. Night bloomers often have an even sweeter fragrance than their day-blooming cousins. Plant with their crowns 4 – 12 inches below the water surface. They thrive in intense sun but are highly sensitive to frost and dislike cool weather. Tropical night-blooming water lilies are hardy in zones 10-11.
DWARF OR MINIATURE WATER LILIES (Nymphaea spp) Dwarf species share qualities with other water lilies, but they spread to only 1 - 2 feet. That makes them an excellent candidate for small ponds and container gardens. Their flowers are smaller, also, a diminutive 1 – 5 inches across. For their size, they are prolific bloomers, sometimes producing two to three dozen flowers at a time. The quality of their blooms, though, is less than that of their big cousins. Mini lilies come in fewer colors than full-sized plants. Plant dwarfs 5 – 10 inches deep with their crowns 4 - 10 inches below the surface of the water. They are hardy generally in zones 4-11, but their hardiness will vary among cultivars.
LOTUSES (Nelumbo spp) Lotuses have large, exotic flowers with unusual centers, making them ideal for dried flower arrangements. Blooms often exceed 6 inches across. Unlike water lilies, the flower stalks rise up to 5 feet above floating leaves. Flowers are intensely fragrant, can perfume an entire corner of the garden, and are available in many colors. Miniature varieties of lotuses, including bowl lotuses, are gaining in popularity. They have flower stalks that grow only 1 - 3 feet above the surface, making them more practical for most ponds. Plant lotuses in full sun with their crowns 2 - 12 inches below the surface of the water. They'll need several weeks with temperatures of 80° F or higher to bloom well. Lotuses are hardy in zones 4 - 11, with their hardiness varying among cultivars.